Lightning arrester, gas flow type



G. B. ROLCSON LIGHTNING ARRESTER GAS FLOW TYPE Filed Jan. 20, 1942 3mm QLKf/f/yozosom sept. 14, 1943.

Patented Sept. v14, 1943 LIGHTNING ARRESTER, G'AS FLOW TYPE Glenn B. Roloson, Crestone, Colo. Application January zo, 1942, serial No. 427,429

4 Claims. (CL F75- 30) (Granted under the act ot March 3, 1883, as amended April 30, 1928;v 370 O. G. '157) The invention described herein may be manufactured and used by or for the Government of the United States for governmental purposes without the payment to me of any royalty thereon in accordance with the provisions of the act of April 30, 1928 (Ch. 460, 45 Stat. L. 467).

My invention pertains to an electric discharge and arc interrupting device for the prevention of interruption to service and damage to connected apparatus due to surges produced by lightning or other causes.

The function of the device is to discharge surge currents produced by lightning or other causes and to interrupt the power follow up currents in the shortest possible time, but without destruction to the device.

The purpose of gas evolving material in lightning arresters is two-fold, first to non-ionize the arc paths and second, by the expanding force of freed gases, to blow out the arc. Considerable difliculty has been experienced, however, in controlling the gases sufficiently to perform their full intended function without so restricting the iiow of gases as will cause them to burst the electric discharge and arc interrupting device.

The present invention aims to provide a device of the character having ample passageway for the non-destructive iiow of the gases and yet provide for controlling the gas flow to insure an interception of all arc paths thereby.

The foregoing and other objects of the invention will become apparent from a reading of the following specification and appended claims. Certain embodiments having the characteristics of my invention and by which the same may be practiced are illustrated in the accompanying drawing in which:

' Figure 1 is an elevational view of a preferred embodiment partially broken away to illustrate incorporated features of my invention;

Figure 2, a longitudinal cross-section of the embodiment illustrated in Figure 1; and

Figures 3 and 4, cross-sectional views taken at lines 3 3 and 4-4 of Figure 1.

With reference to the embodiment illustrated in the drawing, there is provided a di-electric tube I of fiber, solid boric acid or other material capable of evolving a considerable quantity of substantially non-ionized gas when subjected to the heat of an electric discharge in close proximity therewith. The tube is closed at both ends II and I2 and is provided with a series of vents I3 spaced one above the other in one side wall of the tube. Tipped electrodes I4 and I5 are positioned within the ends of the tube I0 with their apices innermost, in spaced discharge relation and immediately adjacent the side wall of the tube in which the vents I3 are provided. The positioning of the arcing tips of the electrodes on the vented side of the tube fixes the shortest arc path on a line traversing the vents.

For convenience in manufacture and assembly the electrodes are carried by terminal posts I6 and l1 to which leads I8 and I9 may be secured. The terminal posts may also serve as means for closing the ends II and I2 of the tube I0 to pre vent the escape of gases created within the chamber of the tube except through vents I3.

A tube 20, such as fiber, plastic, glass or other material having suitable insulating strength and Weather resisting qualities, is mounted eccentrically outside of the first described tube I0. The larger tube 20 is closed at its upper end but is provided with an opening 2| for the gas dischargeI at its lower end. The outer tube 20 functions to prevent the discharge gases from causing a liashover to or between live line parts and also to prevent moisture from entering the inner tube through' the vents I3. f

It will be understood from the foregoing description that gases evolved within the tube Ill by reason of an arc owing between the apices of the electrodes I4 and I5 will be forced by their own accumulation from the chamber of the tube through the vents I3 directly across an arc flowing between the electrodes, and once discharged into the chamber of the outer tube 20 are free to flow therefrom through the opening 2|. The gases iiowing from the chamber of the tube I0 are forced across the arc at each of the vents I3, the vents thereby operating to cause non-ionized gas to be introduced directly into the arc and simultaneously weaken it to a final breaking point at one or more of the vents. The path of the gases iiowing from the chamber of tube I il also tends to hold an arc iiowing between the electrodes against the side wall of the tube in which the vents are located, thereby insuring an interception of the arc by the gas streams flowing through the vents. The vents are of such size as will allow suilcient amounts of gases to freely escape before accumulating to an extent sufficient to cause a bursting of the tube.

Having described my invention and illustrated an embodiment whereby the same may be practiced, what I claim is:

1. An electric discharge and arc interrupting device comprising the combination of a tubular member of iii-electric material capable of evolving non-ionized gases when subjected to the heat of an arc in close proximity therewith, said tubular member having a plurality of aligned vents spaced one above the other through one side wail, means closingr the ends of said tubular member and cooperating with said tubular member to form a vented gas chamber, spaced electrodes, the shortest arc path between which lies immediately adjacent the inner surface of said tubular member traversingly of the inner mouths of said vents, terminal means extending from said electrodes for connecting the device in a circuit, and a vented housing or" insulating material surrounding said tubular member and eccentric therewith therebjir forming a chamber of substantiallir crescent-shaped cross-section into which the vents of said tubular member open.

2. An electric discharge and arc interrupting device comprising the combination of a housing oi (ii-electric material capable of evolving' noniomzed gases when subjected to the heat oi an arc in close proximity therewith, a pair ci electrodes spaced from one another within said housing on a line immediately adjacent an inner wall of said housing, said housing having at least one vent through the wall along which extends the shortest line between said electrodes wherethe shortest are path between said electrodes crosses the mouth of said vent, terminal means extending from said electrodes for connecting the device in a circuit, and a protective casing oi insulating material encasing said housing and forming a chamber into which said vent opens, said casing having an opening in the bottom portion thereof for the escape of gases.

3. An electric discharge and arc interrupting device comprising the combination of inner and outer tubular members of di-electric material one mounted eccentrically within the other, the

inner tubular member being of material capable o! evolving non-ionized gases when subjected to the heat of an arc in close proximity therewith, a pair of electrodes closing the ends of the inner tubular member and having tipped portions extending into the hoiiow of said inner tubular member on a line immediately adjacent an in ner side wall thereof, said inner tubular member having at least one vent through the side wall along which extends the shortest line between said electrodes whereby the shortest arc path between said electrodes crosses the mouth of said vent, terminal means extending from said electrodes for connecting the device in a f circuit, and means closing one end of said outer tubular member and securing said tubular members in fixed relation.

d. An electric discharge and arc interrupting device comprising the combination of a tubular member of di-eiectric material capable of evolving non-ionized gases when subjected to the heat of an arc in close proximity therewith, said tubular member having a plurality of aligned vents spaced one above the other through one side wall, means ciosing the ends of said tubular member and cooperating with said tubular member to form a vented gas chamber, spaced electrodes, the shortest arc path between which lies immediately adjacent the inner surface of said tubular member traversingly of the inner mouths of said vents, terminal means extending from said electrodes for connecting,r the device in a circuit, and a vented housing of plastic material surrounding said tubular member and eccentric therewith thereby forming a chamber of substantially crescent-shaped cross-section into which the vents of said tubular member open,

GLENN l,` ROLOSON. 

